Investigations have centered on understanding on a molecular level the intracellular regulation of metabolism in a neuroendocrine organ, the pineal gland. The topics of specific interest include the factors regulating cyclic AMP production, the function of cyclic AMP, the control of synthesis of pineal N-acetyltransferase activity, the control of activation and inactivation of this enzyme and related enzymes, the role of mRNA synthesis in the regulation of the activity of N-acetyltransferase activity, the regulation of pineal biopterin and control of guanosine cyclohydrolase.